In the evaluation of the molecular structure of a material by neutron scattering/diffraction measurement, the structural information can be calculated based on the neutron scattering length density of the target material. Here, in the case of scattering of the incident (neutron) wave from a single spinless atomic nucleus, the neutron scattering length indicates the degree of neutron scattering from this atomic nucleus, and is calculated by dividing the scattering length by the density of the target material.
Thus, the neutron scattering length density of single-composition target materials can be simply determined depending on the kind, the number and the density of the atoms in the target. On the other hand, in the case of non-single-composition target materials, for example, a target material that is a mixture of multiple components, with their ratio not determined, it is difficult to accurately determine the neutron scattering length density of the target materials.